Applications of Metabolomics in Calcium Metabolism Disorders in Humans.

The pathogenesis of the disorders of calcium metabolism is not fully understood. This review discusses the studies in which metabolomics was applied in this area. Indeed, metabolomics could play an essential role in discovering biomarkers and elucidating pathological mechanisms. Despite the limited bibliography, the present review highlights the potential of metabolomics in identifying the biomarkers of some of the most common endocrine disorders, such as primary hyperparathyroidism (PHPT), secondary hyperparathyroidism (SHPT), calcium deficiency, osteoporosis and vitamin D supplementation. Metabolites related to above-mentioned diseorders were grouped into specific classes and mapped into metabolic pathways. Furthermore, disturbed metabolic pathways can open up new directions for the in-depth exploration of the basic mechanisms of these diseases at the molecular level.

MicroRNA Profile Alterations in Parathyroid Carcinoma: Latest Updates and Perspectives.

Parathyroid tumors are a genetically heterogenous group with a significant variability in clinical features. Due to a lack of specific signs and symptoms and uncertain histopathological criteria, parathyroid carcinomas (PCs) are challenging to diagnose, both before and after surgery. There is a great interest in searching for accurate molecular biomarkers for early detection, disease monitoring, and clinical management. Due to improvements in molecular pathology, the latest studies have reported that PC tumorigenesis is strongly linked to the epigenetic regulation of gene expression. MicroRNA (miRNA) profiling may serve as a helpful adjunct in distinguishing parathyroid adenoma (PAd) from PC and provide further insight into regulatory pathways involved in PTH release and parathyroid tumorigenesis. So far, only a few studies have attempted to show the miRNA signature for PC, and very few overlaps could be found between these relatively similar studies. A global miRNA downregulation was detected in PC compared with normal glands among differentially expressed miRNAs. This review summarizes changes in miRNA expression in PC and discusses the future research directions in this area.

Mutagenic activity of quaternary ammonium salt derivatives of carbohydrates.

This paper presents a study on a series of quaternary ammonium salt (QAS) derivatives of glucopyranosides with an elongated hydrophobic hydrocarbon chain. The new N-[6-(ß-D-glucopyranosyloxy)hexyl]ammonium bromides and their O-acetyl derivatives were analyzed via (1)H and (13)C NMR spectroscopy. The mutagenic activity of the newly synthesized QAS was investigated using two different techniques: The Vibrio harveyi luminescence assay and the Ames test. The obtained results support previous findings contesting QAS safety and indicate that QAS, specifically pyridinium derivatives, might be mutagenic.

A rapid and simple method for detection of type II restriction endonucleases in cells of bacteria with high activity of nonspecific nucleases.

In this work we describe a novel, rapid and simple microscale procedure for identification of restriction endonuclease activity in bacteria lysates, which contain high levels of non-specific DNA nucleases.

Comparison of the use of mussels and semipermeable membrane devices for monitoring and assessment of accumulation of mutagenic pollutants in marine environment in combination with a novel microbiological mutagenicity assay.

A novel microbiological mutagenicity assay, based on bioluminescence of a marine bacterium Vibrio harveyi mutant strain, potentially suitable for monitoring and assessment of mutagenic pollution of marine environment, has been described recently. Here, we tested the use of this assay, in combination with either mussels (Mytilus sp.) or semipermeable membrane devices (SPMDs), in assessment of accumulation of mutagens in marine water (samples of Baltic Sea water were tested). Either similar results were obtained in both systems or higher signals in the SPMD-based system were detected, depending on the tested water samples. We conclude that the use of both mussels and SPMDs in combination with the V. harveyi bioluminescence mutagenicity assay is a method suitable for monitoring and assessment of accumulation of mutagenic pollutants in marine environment, but in some cases the SPMD-based system may provide a more sensitive test.

Rapid detection of mutagens accumulated in plant tissues using a novel Vibrio harveyi mutagenicity assay.

Detection of mutagenic pollution in natural environment is difficult as there are thousands of known chemical mutagens, and they have mutagenic effects usually at very low concentrations. Plants are able to accumulate various substances, including mutagens, in their tissues. Here, we demonstrate that rapid detection of mutagenic activities of compounds accumulated in plant tissues is possible using a recently developed microbiological mutagenicity assay, based on induction of bioluminescence of a dim mutant of a marine bacterium Vibrio harveyi. Using this assay, it was possible to detect mutagenic activity in extracts from relatively small amounts of tissues (1.5 g) collected from plants, which were cultured in vitro for 30 days in the presence of nano-molar concentrations of various chemical mutagens. Moreover, contrary to control samples, cultured in vitro without any mutagens, significant mutagenicity was detected in several extracts of plant tissues collected from natural environment. The whole procedure was as short as 4 h or less.

The use of the Vibrio harveyi luminescence mutagenicity assay as a rapid test for preliminary assessment of mutagenic pollution of marine sediments.

Mutagenic pollution of the natural environment is currently one of the most serious environmental problems. It includes the pollution of marine sediments. Therefore, rapid detection of the presence of mutagens is an important issue. Recently, we have developed a novel microbiological assay for rapid assessment of mutagenicity of samples from the natural environment. This assay is based on bioluminescence of a mutant Vibrio harveyi strain, and was shown to be useful in testing samples of marine water and plant tissues. Here we demonstrate the usefulness of this assay in preliminary assessment of mutagenic pollution of marine sediments. Mutagenicity of environmental samples taken from the Baltic Sea, is documented and compared here with a commercially available standard sediment sample (IAEA 383), which contains known amounts of mutagenic compounds. The whole procedure, from obtaining a sample in the laboratory to getting final results, is very short (less than 4 h).

The use of marine bacteria in mutagenicity assays.

Mutagenic pollution of environment is a global and important problem. This includes marine environment. Although many mutagenicity assays have been developed, there are specific problems with testing marine water and sediments for mutagenic contamination. One of them is the fact that most of genetically modified strains used in commonly available microbiological mutagenicity assays, like Escherichia coli or Salmonella, survive relatively poorly in marine waters, especially those of higher salinity. Thus, alternative assays have been developed, in which bacteria occurring naturally in marine habitats are employed. These assays, reviewed in this article, appear to be useful in testing not only marine samples but also can be used in other approaches, which involve detection and estimation of the amount of mutagenic compounds.

Direct addition of cultures of tester bacteria into semi-permeable membrane devices (SPMDs) as a modified procedure for preliminary detection of mutagenic pollution of the marine environment by use of microbiological mutagenicity assays.

Mutagenic pollution of the natural environment, including marine waters, is a very serious ecological problem. However, since chemical mutagens usually occur and act at low concentrations, their detection and identification is technically difficult, laborious and time-consuming. Therefore, preliminary detection of mutagenic pollution is commonly based on biological mutagenicity assays. On the other hand, triolein-containing semi-permeable membrane devices (SPMDs) provide a method for concentration of hydrophobic organic contaminants, including a large fraction of the mutagens. Combinations of SPMDs with microbiological toxicity and mutagenicity assays have already been described, but only SPMD-derived extracts, prepared with various organic solvents, were tested in such a way to date. We found that the presence of these solvents could interfere with the Vibrio harveyi bioluminescence-based mutagenicity assay. Moreover, preparation of the extracts from SPMD takes usually at least 48h. Here, we propose a modified procedure, based on direct addition of tester bacteria cultures into SPMD. We found that this procedure is significantly (at least two times) more rapid and several times more sensitive than that based on testing the extracts. This optimization is presented in this report. Moreover, we have performed preliminary studies on samples of marine waters. Positive results (i.e. detection of mutagenic activity) were obtained when test samples came from a region known to be highly contaminated by industrial pollution, while negative results were observed in the case of samples from a region supposed to be of low risk for mutagenic pollution.

Optimisation of the microbiological mutagenicity assay based on genetically modified Vibrio harveyi strains.

Recently, we have developed a novel assay designed for detection of mutagenic pollution of the marine environment. This assay is based on the use of a series of genetically modified strains (named BB7, BB7M, BB7X and BB7XM) of a marine bacterium Vibrio harveyi. Sensitivity of the V. harveyi mutagenicity assay was found to be similar to, or even somewhat higher than, that of the commonly used Ames test. Subsequent studies indicated that this assay may be useful in assessment of mutagenic contamination of the marine environment. Nevertheless, we assumed that improvement of this assay is still possible, and thus we aimed to optimise its procedures. Here we present our research on the optimisation of the V. harveyi mutagenicity assay, which indicated that different tester strains used in this assay give the best results depending upon the experimental conditions employed. Incubation of bacteria in a buffer, rather than in a nutrient broth, containing a mutagen, increased the efficiency of the assay with BB7 and BB7M strains, but had a deleterious effect in the case of BB7X and BB7XM. The latter couple of strains revealed higher mutagenicity in the plate assay, as compared to the liquid medium assay. However, the opposite effect was observed for BB7 and BB7M. Low-dose (1 J m(-2)) UV irradiation, as well as 30 min incubation in 0.1 M CaCl2, had no significant effect on the efficiency of the assay when using BB7 and BB7M, whereas the number of mutagen-induced mutants of BB7X and BB7XM strains increased about two times under these conditions. Our previous experiments indicated that various tester strains revealed different sensitivity to particular mutagens. Thus, a series of strains should be used in the assay. Results presented in this report show that different conditions should be used for two pairs of the tester strains: BB7 and BB7M, and BB7X and BB7XM.